Test system and test contactor for electronic modules having beam spring contacts

ABSTRACT

A pass through test system for testing an electronic module includes an interface board, and test contactors movably mounted to the interface board for electrically engaging terminal contacts on the module with a zero insertion force on the modules. The interface board is configured for mounting to an automated or manual pass through test handler in electrical communication with test circuitry. In a first embodiment the interface board includes test pads in electrical communication with the test circuitry, and rotatable test contactors having spring contacts configured to simultaneously engage the test pads and the terminal contacts on the module. In a second embodiment the interface board includes test pads in electrical communication with the test circuitry, and slidable test contactors having beam leads configured to simultaneously engage the test pads and the terminal contacts on the module. In a third embodiment the test contactors are slidably mounted to the interface board, and include coiled spring contacts in electrical communication with a flex circuit. A test method includes the steps of: providing the test contactors, electrically engaging the terminal contacts on the module with a zero insertion force using the test contactors, and then applying test signals through the test contactors and the terminal contacts to the module.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a division of Ser. No. 09/650,161, filed on Aug. 28,2000, now U.S. Pat. No. 6,483,329.

FIELD OF THE INVENTION

This invention relates generally to the testing of electronic modules,and more particularly to a test system, a test contactor and a testmethod for testing electronic modules.

BACKGROUND OF THE INVENTION

Electronic modules, such as semiconductor memory modules, multi chipmodules, semiconductor carriers, semiconductor packages, andmicroprocessors are routinely tested during manufacture. The modulesinclude terminal contacts in electrical communication with theelectronic devices contained on the modules. For performing various testprocedures on the modules, temporary electrical connections are made tothe terminal contacts.

One type of prior art electronic module 10, which is illustrated inFIGS. 1A and 1B, includes a substrate 12, and multiple semiconductorpackages 16 mounted to the substrate 12. The module 10 also includes arow of terminal contacts 14 on the substrate 12 in electricalcommunication with the integrated circuits contained on thesemiconductor packages 16. The terminal contacts 14 comprise generallyplanar, in-line metal pads located on opposing sides of the substrate 12along a lateral edge 18 thereof. The substrate 12 typically comprises anelectrically insulating material such as a glass filled plastic (FR-4),or a ceramic. In addition, the substrate 12 includes through openings 19which facilitate indexing and handling by automated test equipment andcarriers.

For testing the electronic module 10 test systems have been developedand are commercially available from various manufacturers. These testsystems are configured to make temporary electrical connections with theterminal contacts 14. In addition, the test systems are configured toapply test signals through the terminal contacts 14 to the electronicdevices on the module 10, and then to analyze the response signals fromthe electronic devices. Often times these test systems merely test thegross functionality of the module 10, as the semiconductor packages 16on the module 10 have been previously individually tested and burned-in.

The test systems typically include test boards and test circuitry inelectrical communication with the test boards. In addition, the testboards typically include interface boards having test contactorsconfigured to physically and electrically engage the terminal contacts14 on either side of the module 10. In general there are two types oftest systems, which are sometimes referred to as “pass through testsystems”, or “socket test systems”.

FIG. 1C illustrates a pass through test system 11PT having an interfaceboard 13PT, and test contactors 15PT on the interface board 13PT. Thetest contactors 15PT are in electrical communication with test circuitry(not shown). In addition, the test contactors 15PT are movable from aninactive (open) position in which the terminal contacts 14 on the module10 are not engaged, to an active (closed) position in which the terminalcontacts 14 on the module 10 are physically and electrically engaged.

As shown in Figure 1C, with the test contactors 15PT in an inactive(open) position, the module 10 can be indexed into a contactor areabetween the test contactors 15PT, as indicated by arrow 17PT. With themodule 10 located in the contactor area, the test contactors 15PT can bemechanically moved to the active (closed) position to physically andelectrically engage the terminal contacts 14. The pass through testcontactors 15PT are sometimes referred to as being “zero insertionforce” (ZIF) contactors because temporary electrical connections can bemade without an insertion force being placed on the module 10.

FIG. 1D illustrates a socket test system 11S having an interface board13S, and test contactors 15S on the interface board 13S. In this case,the test contactors 15S are normally in an active (closed) position, butare mechanically moved to an inactive (open) position as the module 10is inserted from above as indicated by arrow 17S. When the module 10 isin place, the test contactors 15S move back to the active (closed)position to physically and electrically engage the terminal contacts 10.The socket test contactors 15S are sometimes referred to as being “lowinsertion force” (LIF) contactors because an insertion force is exertedon the module 10 in making the temporary electrical connections with thetest contactors 15S.

One advantage of the pass through test system 11PT (FIG. 1C) over thesocket test system 11S, is that no insertion forces are exerted on themodule 10 to provide electrical engagement for testing. Accordingly,less physical stress is placed on the module 10 during testing with thepass through test system 11PT. Also, as the number of terminal contacts14 on the module 10 increases, the insertion forces exerted by thesocket test system 11S increase. The socket test system 11S cantherefore damage the module 10, or the terminal contacts 14 on themodule 10, and can be more expensive to operate and maintain.

The present invention is directed to an improved pass through testsystem. In pass through test systems it is desirable to make temporaryelectrical connections with the terminal contacts 14 on the modules 10that are reliable, and have low electrical resistance. This requiresthat the terminal contacts 14 be scrubbed, or alternately penetrated bythe test contactors 15PT, such that oxide layers and surfacecontaminants on the terminal contacts 14 do not adversely affect thetemporary electrical connections. However, in scrubbing or penetratingthe terminal contacts 14, damage to the terminal contacts 14 and modules10 must be minimized.

It is also advantageous in pass through test systems for the temporaryelectrical connections to provide electrical paths that are short inlength to facilitate the application of high speed test signals, and toprevent capacitive coupling and the introduction of noise and spurioussignals. Further, it is advantageous to make, and then break, thetemporary electrical connections as quickly as possible, to facilitate ahigh throughput for the test procedure.

The pass through test system of the invention includes test contactorsconfigured to make temporary electrical connections that are reliable,have low electrical resistance, and minimally damage terminal contactson the modules. In addition, the test contactors are relativelyinexpensive to make, provide a high throughput, and can be operated in aproduction environment with minimal maintenance. Further, the testcontactors are designed to electrically engage the terminal contactswith a zero insertion force on the module, and to exert a force forretaining the module on the interface board.

SUMMARY OF THE INVENTION

In accordance with the present invention, a pass through test system, apass through test contactor, and a pass through test method for testingelectronic modules are provided. In illustrative embodiments, the testsystem is configured for testing electronic modules having planar,in-line terminal contacts substantially as previously described.

The test system includes test circuitry configured to generate testsignals, and an interface board having contact pads in electricalcommunication with the test circuitry. The interface board can bemounted to a test board of an automated or manual test handlerconfigured to transport, align, and hold the module on edge on theinterface board. The test system also includes test contactors on theinterface board configured to physically and electrically engage theterminal contacts on the module, and to simultaneously physically andelectrically engage the contact pads on the interface board.

In a first embodiment the test contactors include a base rotatably(pivotably) mounted to the interface board, and cantilevered springcontacts on the base configured to simultaneously scrub and penetratethe terminal contacts on the module, and also the contact pads on theinterface board. The base and the spring contacts are rotatable from afirst position (open) in which the terminal contacts are not engaged, toa second position (closed) in which the terminal contacts are physicallyand electrically engaged. Also, the base comprises molded plastic, andthe spring contacts comprise resilient metal leaf springs embedded inthe plastic. The spring contacts include leaf spring end portions forelectrically engaging the terminal contacts on the modules, and leafspring middle portions for electrically engaging the contact pads on theinterface board.

In a second embodiment the test system includes an interface board andslidably mounted test contactors on the interface board. In thisembodiment the test contactors include a base configured for slidingmovement on the interface board, and short beam contacts on the base forsimultaneously electrically engaging the terminal contacts on the moduleand the contact pads on the interface board. Also, the short beamcontacts are oriented at an angle with respect to the surface of thecontact pads and terminal contacts, such that forces are generated formaking and maintaining the temporary electrical connections.

In a third embodiment the test system includes an interface board, andtest contactors mounted on a base slidably mounted to the interfaceboard. The base includes coiled spring contacts configured to generatespring forces for penetrating the terminal contacts. The test systemalso includes a flex circuit in electrical communication with the springcontacts and the test circuitry, configured to allow free slidingmovement of the base on the interface board.

In each of the embodiments, the test contactors are designed toelectrically engage the terminal contacts with a zero insertion force(ZIF) on the module. Movement of the test contactors into the terminalcontacts can be provided by cams, hydraulic cylinders, motors or anysuitable mechanical actuator. In addition, the test contactors aredesigned to penetrate, or to scrub, the terminal contacts duringelectrical engagement, and also to help retain the module on theinterface board. Further, the test contactors are designed for quickengagement and disengagement with the terminal contacts, and aredesigned to provide a relatively short electrical path to the terminalcontacts.

The test method includes the steps of: providing an interface boardcomprising a plurality of contact pads in electrical communication withtest circuitry; providing a plurality of movable test contactors on theinterface board comprising a plurality of spring contacts configured toelectrically engage the terminal contacts and the contact pads with azero insertion force; placing the module on the interface board with theterminal contacts proximate to and aligned with the test contactors;moving the test contactors to physically and electrically engage theterminal contacts and the contact pads with the spring contacts; andapplying test signals through the test contactors and the terminalcontacts to the module.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plan view of a prior art electronic module;

FIG. 1B is a side elevation view of FIG. 1A;

FIG. 1C is a schematic side elevation view of a prior art pass throughtest system,

FIG. 1D is a schematic side elevation view of a prior art socket testsystem;

FIG. 2A is a schematic side elevation view of a first embodiment testsystem constructed in accordance with the invention illustratingrotatable test contactors of the system prior to electrical engagementof terminal contacts on a module under test;

FIG. 2B is a schematic cross sectional view of the test system of FIG.2A taken along line 2B—2B of FIG. 2A;

FIG. 2C is a schematic side elevation view of the test system of FIG. 2Aillustrating the rotatable test contactors during electrical engagementof the terminal contacts on the module under test;

FIG. 2D is a schematic cross sectional view of the test system of FIG.2A taken along line 2D—2D of FIG. 2C;

FIG. 3A is a schematic side elevation view of a second embodiment testsystem constructed in accordance with the invention illustratingslidable test contactors prior to electrical engagement of terminalcontacts on a module under test;

FIG. 3B is a schematic side cross sectional view of the test system ofFIG. 3A taken along line 3B—3B of FIG. 3A;

FIG. 3C is a schematic side elevation view taken along line 3C—3C ofFIG. 3B illustrating a slidable base of the test contactors;

FIG. 3D is a schematic side elevation view of the test system of FIG. 3Aillustrating the slidable test contactors during electrical engagementof the terminal contacts on the module under test;

FIG. 3E is a schematic cross sectional view of the test system of FIG.3A taken along line 3E—3E of FIG. 3D;

FIG. 4A is a schematic side elevation view of a third embodiment testsystem constructed in accordance with the invention illustrating testcontactors on a slidable base prior to electrical engagement of terminalcontacts on a module under test;

FIG. 4B is a schematic side cross sectional view of the test system ofFIG. 4A taken along line 4B—4B of FIG. 4A;

FIG. 4C is a schematic side elevation view of the test system of FIG. 4Aillustrating the test contactors during electrical engagement of theterminal contacts on the module under test; and

FIG. 4D is a schematic cross sectional view of the test system of FIG.4A taken along line 4D—4D of FIG. 4C.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 2A and 2B, a pass through test system 20 constructedin accordance with a first embodiment of the invention, and configuredto test electronic modules 10, is illustrated. The test system 20includes an interface board 22, and a plurality of test contactors 24rotatably mounted to the interface board 22 configured to make temporaryelectrical connections with the terminal contacts 14 on the module 10.

As used herein, the term “pass through test system” means a test systemin which temporary electrical connections are made with the terminalcontacts 14 on the module 10 with a “zero insertion force”. As usedherein, the term “zero insertion force” means that no forces are beingexerted on the module 10 to move the test contactors 24 in making thetemporary electrical connections.

The interface board 22 is configured to support the module 10 on theedge 18 thereof substantially as shown. The interface board 22 isconfigured for mounting to an automated or manual pass through testhandler (not shown). Support, movement and indexing of the module 10 canbe provided by the test handler Suitable automated pass through testhandlers are commercially available from Advantest Corporation, Tokyo,Japan, as well as other manufacturers.

The interface board 22 comprises an electrically insulating material,such as molded plastic, a glass filled resin (e.g., FR-4) or a ceramic.In addition, the interface board 22 includes a pattern of contact pads26 in electrical communication with test circuitry 28. The testcircuitry 28 is configured to generate and apply test signals to theintegrated circuits contained on the module 10, and to analyze theresultant signals. Suitable test circuitry is commercially availablefrom Advantest Corporation of Tokyo, Japan, Teradyne of Boston, Mass.,as well as other manufacturers.

The contact pads 26 are formed in a pattern (size and spacing) thatmatches a pattern of the terminal contacts 14 on the module 10. Thecontact pads 26 can comprise a highly conductive metal, such as copperor aluminum. In addition, the interface board 22 can include conductors30 such as conductive traces and metal filled vias that electricallyconnect the contact pads 26 to the test circuitry 28.

The test contactors 24 are configured to establish electricalcommunication between the terminal contacts 14 on the module 10, and thecontact pads 26 on the interface board 22. The test contactors 24include a rotatable (pivotable) base 32, and cantilevered springcontacts 34 on the base 32. Different constructions of the base 32 andthe spring contacts 34 are possible. However, in the illustrativeembodiment the base 32 comprises molded plastic, and the spring contacts34 are molded integrally to the base 32. Suitable plastics for the base32 include polyetherimide (PEI), polyethersulfone (PES), polyarylsulfone(PAS), polyphenylene sulfide (PPS), liquid crystal polymer (LCP), andpolyether-ether ketone (PPEK). The spring contacts 34 preferablycomprise a resilient metal, such as a copper alloy (e.g., berylliumcopper), stainless steel, or a nickel-iron alloy.

The interface board 22 includes support members 36 on either endconfigured to support the base 32 for rotatable (pivotable) motion. Thesupport members 36 can be molded integrally to the interface board 22,or can comprise separate members attached to the interface board 22. Adrive mechanism 38 (FIG. 2B) is operably associated with the base 32,and is configured to rotate (pivot) the base 32, and the spring contacts34, from the “open” (inactive) position of FIGS. 2A and 2B, to the“closed” (active) position of FIGS. 2C and 2D. The drive mechanism 38can comprise a cam, a motor, a spring or other suitable actuatormechanism. In addition, the drive mechanism 38 can be a component of thetest board or the test handler to which the interface board 22 ismounted.

Referring to FIGS. 2C and 2D, the spring contacts 34 include leaf springtip portions 40 configured to physically and electrically engage theterminal contacts 14 on the module substrate 12 with a zero insertionforce. In addition, the spring contacts 34 include leaf spring middleportions 42 configured to physically and electrically engage the contactpads 26 on the interface board 22. The leaf spring tip portions 40 andthe leaf spring middle portions 42 are flat planar springs formed from asingle piece of metal but oriented in opposite directions from an axisof the spring contacts 34. In the “closed” (active) position of therotatable base 32, the spring contacts 34 establish electricalcommunication between the terminal contacts 14 on the module substrate12, and the contact pads 26 on the interface board 22. This electricalcommunication provides a plurality of separate electrical paths betweenthe test circuitry 28, and the integrated circuits contained on thesemiconductor packages 16.

The construction of the spring contacts 34 provides several advantagesfor applying test signals to the module 10. One advantage is that theleaf spring tip portions 40 of the spring contacts 34 scrub the terminalcontacts 14 on the module substrate 12 as the spring contacts 34 arerotated with the base 32 into the closed position. This scrubbing actionscrubs and penetrates oxide layers on the terminal contacts 14, whichprovides low resistance temporary electrical connections. Anotheradvantage is that the spring contacts 34 exert spring forces formaintaining the electrical connections, and also exert spring forces forholding the module 10 on the interface board 22.

Yet another advantage is that the electrical paths between the terminalcontacts 14 and the contact pads 26 are relatively short, such thatimpedance, cross talk, and capacitive coupling are reduced. Stillanother advantage is that the temporary electrical connections can bemade for testing, and then quickly disconnected following testing by therotary motion of the spring contacts 34. The rotary motion thus providesa high throughput and a low dwell time for testing multiple modules 10in a production environment. In addition, the spring contacts 34 arerelatively robust and are able to withstand abuse in a productionenvironment. Still further, the spring contacts 34 make the temporaryelectrical connections with the terminal contacts 14 without aninsertion force being exerted on the module 10 (i.e., zero insertionforce).

In the illustrative embodiment, the spring contacts 34 are configured toelectrically engage the terminal contacts 14 on only one side of themodule 10 along the edge 18 thereof. However, pairs of spring contacts34 can also be configured to electrically engage the terminal contacts14 on opposing sides of the module 10. For example, the spring contacts34 can be configured to electrically engage every other terminal contact14 on a first side of the module 10, while opposing spring contacts 34can be configured to electrically engage every other terminal contact 14on a second side of the module 10.

Also, the spring contacts 34 can be configured to electrically engageother types of terminal contacts than the flat planar terminal contacts14 shown in the illustrative embodiments. For example, the springcontacts 34 can be configured to electrically engage bumped contacts(e.g., solder balls in a ball grid array), pin contacts (e.g., pins in apin grid array), and various lead type contacts (e.g., stand off leads,j-bend leads).

Referring to FIGS. 3A and 3B, a pass through test system 20A constructedin accordance with a second embodiment of the invention is illustrated.The test system 20A includes an interface board 22A, and a plurality oftest contactors 24A slidably mounted to the interface board 22A. Theinterface board 22A is configured to support the module 10 on the edge18 thereof substantially as shown. In addition, the interface board 22Ais configured for mounting to an automated or manual pass through testhandler, substantially as previously described. Further, the interfaceboard 22A includes contact pads 26A, and conductors 30A in electricalcommunication with the test circuitry 28 substantially as previouslydescribed.

The test contactors 24A are configured to establish electricalcommunication between the terminal contacts 14 on the module 10, and thecontact pads 26A on the interface board 22A, with a zero insertion forceon the module 10. The test contactors 24A include a slidable base 32A,and a plurality of short beam spring contacts 34A on the base 32A.Different constructions of the base 32A and the spring contacts 34A arepossible. However, in the illustrative embodiment the base 32A comprisesmolded plastic, and the spring contacts 34A comprise metal beams moldedintegrally to the base 32A.

Further, the interface board 22A includes support members 36A onopposing ends thereof configured to support the base 32A for slidablemotion over the planar surface of the interface board 22A. As shown inFIG. 3C, each support member 36A includes a slot 44A, and the base 32Aslides within the slot 44A. The support members 36A can be moldedintegrally to the interface board 22A, or can comprise separate membersattached to the interface board 22A. A drive mechanism 38A (FIG. 3B) isoperably associated with the base 32A, and is configured to slide thebase 32A and the spring contacts 34A from the “open” (inactive) positionof FIGS. 3A and 3B, to the “closed” (active) position of FIGS. 3D and3E.

The drive mechanism 38A can comprise a cam, a motor, a hydrauliccylinder, a spring or other suitable mechanical, hydraulic or electricalmechanism. In addition, the drive mechanism 38A can be a component ofthe test handler, to which the interface board 22A is mounted. Thestroke or movement of the base 32A can be controlled by the design ofthe drive mechanism 38A. In addition, the drive mechanism 38A can bedesigned to “overdrive” the spring contacts 34A into the terminalcontacts 14 by a selected amount.

Referring to FIGS. 3D and 3E, the short beam spring contacts 34A includespring tip portions 40A configured to physically and electrically engagethe terminal contacts 14 on the module substrate 12. Rather thanscrubbing the terminal contacts 14, as with the previous embodiment, thetip portions 40A are configured to penetrate the terminal contacts 14 tocontact the underlying metal. In addition, the short beam springcontacts 34A include end portions 42A configured to physically andelectrically engage the contact pads 26A on the interface board 22A. Inthe “closed” (active) position of the slidable base 32A, the short beamspring contacts 34A establish electrical communication between theterminal contacts 14 on the module substrate 12 and the contact pads 26Aon the interface board 22A. This electrical communication provideselectrical paths between the test circuitry 28, and the integratedcircuits contained on the semiconductor packages 16.

As also illustrated in FIGS. 3D and 3E, the short beam spring contacts34A are angled with respect to the planar surfaces of the terminalcontacts 14 and the contact pads 26A. This configuration allows theshort beam spring contacts 34A to exert spring forces on both theterminal contacts 14 and the contact pads 26A. These spring forces helpto maintain the temporary electrical connections and to retain themodule 10 on the interface board 22A. In the illustrative embodiment theangle of the short beam spring contacts 34A with respect to the terminalcontacts 14 and the contact pads 26A is about 45′.

Referring to FIGS. 4A and 4B, a pass through test system 20B constructedin accordance with a third embodiment of the invention is illustrated.The test system 20B includes an interface board 22B, and a plurality oftest contactors 24B slidably mounted to the interface board 22B. Theinterface board 22B is configured to support the module 10 on the edge18 thereof substantially as shown. In addition, the interface board 22Bis configured for mounting to an automated or manual pass through testhandler, substantially as previously described.

The test contactors 24B are configured to establish electricalcommunication between the terminal contacts 14 on the module 10, and thetest circuitry 28 with a zero insertion force being exerted on themodule 10. The test contactors 24B include a slidable base 32B, andcoiled spring contacts 34B on the base 32B. In this embodiment a flexcircuit 30B is in electrical communication with the spring contacts 34B.The flex circuit 30B is designed to move with the slidable base 32B asthe coiled spring contacts 34B engage and disengage the terminalcontacts 14 on the module 10. As with the previous embodiments, the base32B can comprise molded plastic, and the coiled spring contacts 34B canbe molded integrally to the base 32B.

Also, the interface board 22B includes support members 36B on eitheropposing end thereof configured to support the base 32B for slidablemotion. The support members 36B can be molded integrally to theinterface board 22B, or can comprise separate members attached to theinterface board 22B. A drive mechanism 38B (FIG. 4B) is operablyassociated with the base 32B, and is configured to slide the base 32Band the spring contacts 34B from the “open” (inactive) position of FIGS.4A and 4B, to the “closed” (active) position of FIGS. 4C and 4D.

The drive mechanism 38B can comprise a cam, a motor, a spring or othersuitable mechanism. In addition, the drive mechanism 38B can be acomponent of the pass through test handler, to which the interface board22B is mounted. The stroke or movement of the base 32B can be controlledby the design of the drive mechanism 38B. In addition, the drivemechanism 38B can be designed to “overdrive” the spring contacts 34Binto the terminal contacts 14 by a selected amount.

Referring to FIGS. 4C and 4D, the spring contacts 34B include spring tipportions 40B configured to physically and electrically engage theterminal contacts 14 on the module substrate 12. Rather than scrubbingthe terminal contacts 14, as with the previous embodiment, the tipportions 40B are configured to penetrate the terminal contacts 14 tocontact the underlying metal. In this embodiment the tip portions 40Bare attached to spring coils 46B, that enhance the spring force exertedby the tip portions 40B during electrical engagement of the terminalcontacts 14. In particular, as shown in FIGS. 4C and 4D the spring coils46B function to exert torsional spring forces on the tip portions 40Bfor penetrating the terminal contacts 14. The spring contacts 34B alsoinclude end portions 42B in electrical communication with the flexcircuit 30B. In addition, the spring contacts 34B include a singlesupport pin 48 which is located in the open center portions of thespring coils 46B, and is configured to provide support and retention forthe spring contacts 34B.

In the “closed” (active) position of the slidable base 32B, the springcontacts 34B establish electrical communication between the terminalcontacts 14 on the module substrate 12 and the flex circuit 30B. Thiselectrical communication provides electrical paths between the testcircuitry 28, and the integrated circuits contained on the semiconductorpackages 16.

Thus the invention provides a pass through test system, a pass throughtest contactor, and a pass through test method for electronic modules.Although the invention has been described with reference to certainpreferred embodiments, as will be apparent to those skilled in the art,certain changes and modifications can be made without departing from thescope of the invention, as defined by the following claims.

I claim:
 1. A system for testing an electronic module having a pluralityof terminal contacts comprising: a test circuitry configured to generateand apply test signals to the module; a board comprising a plurality ofcontacts in electrical communication with the test circuitry; and aplurality of beam contacts on the board movable from a first position inwhich the terminal contacts can be aligned with the beam contacts with azero insertion force on the module, to a second position in which thebeam contacts simultaneously electrically engage the terminal contactsand the contacts, each beam contact comprising a first portionconfigured in the second position to electrically engage a contact onthe board, and a second portion configured in the second position toelectrically engage a terminal contact on the module.
 2. The system ofclaim 1 wherein the second portion is configured to penetrate theterminal contact.
 3. The system of claim 1 wherein the first portioncomprises a first end of the beam contact and the second portioncomprises a second end of the beam contact.
 4. The system of claim 1wherein the board comprises at least one support and the beam contactscomprise a base slidably mounted to the at least one supports.
 5. Thesystem of claim 1 wherein the contacts comprise planar pads.
 6. Thesystem of claim 1 wherein the module comprises an element selected fromthe group consisting of semiconductor memory modules, multi chipmodules, semiconductor carriers, semiconductor packages, andmicroprocessors.
 7. A system for testing an electronic module having aplurality of terminal contacts comprising: a test circuitry configuredto generate and apply test signals to the module; a board comprising aplurality of contact pads in electrical communication with the testcircuitry; a plurality of contacts on the board movable from a firstposition in which the terminal contacts can be aligned with the contactswith a zero insertion force on the module to a second position in whichthe contacts simultaneously electrically engage the contact pads and theterminal contacts, each contact comprising a first spring tip portionconfigured to electrically engage a contact pad on the board in thesecond position, and a second spring tip portion configured to penetratea terminal contact on the module in the second position.
 8. The systemof claim 7 the contacts comprise angled beams.
 9. In a test systemincluding a test circuitry for applying test signals to an electronicmodule having a plurality of terminal contacts and a board having aplurality of contact pads in electrical communication with the testcircuitry, a test contactor for establishing electrical communicationbetween the test circuitry and the module comprising: a plurality ofbeam spring contacts on the board movable from a first position in whichthe terminal contacts can be aligned with the beam spring contacts witha zero insertion force on the module, to a second position in which thebeam spring contacts simultaneously electrically engage the terminalcontacts and the contact pads, each beam spring contact comprising afirst spring tip portion configured in the first position to be spacedfrom a contact pad and in the second position to electrically engage thecontact pad, and a second spring tip portion configured in the firstposition to align with a terminal contact and in the second position topenetrate the terminal contact.
 10. The test contactor of claim 9further comprising a base for the beam spring contacts slidably mountedto the board.
 11. The test contactor of claim 9 further comprising atest handler configured to move the beam spring contacts from the firstposition to the second position.